


In the Commander's Quarters

by hedduh



Category: Shingeki no Kyojin | Attack on Titan
Genre: Anal Fingering, Anal Sex, Bottom Erwin Smith, Dirty Talk, First Kiss, First Time, Frottage, M/M, Massage, Oral Sex, PWP, Rimming, Smut, it's just smut, versatile
Language: English
Status: In-Progress
Published: 2018-03-17
Updated: 2018-11-19
Packaged: 2019-04-01 09:21:58
Rating: Explicit
Warnings: Underage
Chapters: 5
Words: 10,799
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13995243
Author URL: https://archiveofourown.org/users/hedduh/pseuds/hedduh
Summary: Erwin has caught himself admiring the young man many times over the past few months, and more than a few times, he’s caught Armin looking back.





	1. Chapter 1

With this morning’s strategy meeting coming to an end, Erwin sits back at his desk and asks, “Alright, any questions?” When none are forthcoming, he nods. “Dismissed.”

As the room begins to clear, his eyes find themselves drawn to a certain blond cadet. It’s certainly not a new occurrence. Erwin has caught himself admiring the young man many times over the past few months, and more than a few times, he’s caught Armin looking back. He thinks it’s probably time to clarify his intentions. “Armin,” he calls, “a moment, please?”

Armin approaches his desk as the room empties.

“I’d like to ask you a question, Armin, but first I want to make it clear that I’m not speaking to you as your Commander right now, just a man on equal footing as yourself.”

Armin blinks at the unexpected request. Curious, he nods his permission.

Erwin leans forward to clasp his hands together atop his desk. “I would very much like to spend the night with you. Would you consent to visit my quarters tonight?”

Armin’s eyes widen and a blush rises to his cheeks. He looks down bashfully and chews his bottom lip. “I…”

“I don’t want to pressure you, Armin,” he says, straightening in his chair. “Take some time to think about it. If you decide you’d like to join me, I’ll be here after evening meal. If you choose not to, I’ll understand.”

“Okay,” he answers, nodding to himself. “I’ll consider it.”

“Thank you.” 

Armin gives him a small smile and turns to leave. He’s about to close the door behind him when Erwin calls his name again.

“Yes?” he asks, turning to lock eyes with Erwin again.

“There’s no time limit on this, so take as long as you need. It doesn’t have to be tonight.”

Armin nods and backs out into the hallway with a soft “Thank you… Erwin.” before the door closes.

-

Erwin’s at his desk, his jacket cast off but still partially in uniform aside from the belts missing from his top half, sleeves rolled up and top two buttons undone. He’s finishing some paperwork before bed when there’s a soft knock on his door. “Come!”

He flicks his eyes toward the door to see Armin slipping inside. He’s wearing loose fitting sleep clothes and his hair looks slightly damp from the showers. They regard each other silently for a moment until Erwin turns in his chair and holds out his arm to beckon Armin closer. 

Armin approaches, nervously gripping the bottom of his sleep shirt. He stops when he’s directly in front of Erwin and Erwin’s large hand settles hot against the small of his back.

“Will you sit with me while I finish this up? It will only take a few minutes.”

Armin nods and Erwin guides him forward between his spread legs to seat him on Erwin’s left leg, Erwin’s hand never leaving his back.

Erwin pushes a soft kiss to his temple and begins rubbing a soothing pattern against Armin’s back with his thumb, before turning his attention back to his work. He feels Armin slowly begin to relax against him as Erwin scratches ink over paper.

As Armin’s weight leans more against Erwin’s chest, it leaves Erwin’s hand free to roam up and down his back and around to squeeze at his waist and hip. Armin lets out a soft sigh and rests his head on Erwin’s shoulder, then nestles his forehead into Erwin’s neck.

Erwin squeezes his outer thigh in response and finally signs his name at the bottom of his document. He leaves it to dry for a moment while packing up his ink and supplies one handed and storing them in a desk drawer. The documents are then stored away in another.

Now freed from his task, Erwin lifts Armin’s face to his with a guiding finger under his chin. He tilts his face and closes the short distance between them until their lips are scant centimeters apart, where he pauses, looking into Armin’s eyes. “May I?”

A whispered “Yes” is his response and Armin closes his eyes as Erwin presses gently against his lips. 

Armin’s lips are warm and soft, though his movements are a bit clumsy. Erwin suspects he may be taking the boy’s first kiss, so he aims to make it as good as possible. The arm wrapped around Armin’s back tightens to hold him close and secure as his other hand slips up from Armin’s chin to cup the side of his face to keep him in the perfect position. He continues the languorous presses of lips against lips until Armin seems more confident in his actions.

He runs his tongue against Armin’s lower lip, sucking it lightly between his own and releasing it to apply pressure to the seam of Armin’s lips, encouraging them to part. When he licks inside, he finds Armin’s tongue already pressing forward to meet his and in his surprise, Erwin lets out a pleased moan. Armin inhales deeply and digs his fingers into Erwin’s shoulders as they lick into each other’s mouths. Erwin pushes deeper, the feeling of their tongues sliding seductively against each other in the hot cavern of Armin’s mouth has him slowly hardening in his pants. His hands begin to roam Armin’s body more feely and Erwin drinks in the soft sounds of Armin’s pleasure.

He slides his hands under Armin’s shirt to begin pushing the fabric upwards and pulls away from Armin’s mouth just long enough to remove it completely before continuing their kiss. He’s incredibly pleased to feel Armin’s fingers pulling at the buttons of his own shirt seconds later. When Armin slips the final button free, he leans back to push Erwin’s shirt open, licking his lips as his eyes devour Erwin’s muscular chest. He runs his hands over Erwin’s pecs, sucking on his bottom lip when the brush of his fingers over Erwin’s nipple causes the muscles there to twitch and flex. He watches the play of muscles in Erwin’s thick arms as he shrugs the shirt off completely.

Erwin takes this time to watch Armin, notes the slight flush on his cheeks, his dilated pupils, his parted lips. The backs of his fingers brush up the side of Armin’s cheek. “Beautiful.”

Armin’s eyes snap up and a deep flush appears on his face as he meets Erwin’s gaze. Erwin smiles when he realizes he can feel the heat of it under his fingers. “Stand up for me?”

Armin nods and slips forward to stand between Erwin’s legs once again. Erwin’s large hands on his hips keep him close enough to Erwin that he barely has to lean forward to initiate another kiss. Armin’s hands settle on Erwin’s shoulders before sliding down his arms, marveling at the size of them as Erwin unfastens Armin’s pants and pushes them down his slim hips along with his underwear. Erwin waits for Armin to step out of them before sliding one arm around and under Armin’s ass and the other up his back to grip at his shoulder, standing and lifting Armin to deposit him on the desk.

Armin makes a small noise of complaint when his bare skin touches the cool wooden surface, but is distracted quickly enough when Erwin sucks one last time on his tongue and starts trailing wet, open-mouthed kisses down to his neck.

Armin’s hands slide into Erwin’s hair and he tilts his head to the side when Erwin begins sucking and nibbling at his neck. He’s breathing heavily through his mouth now, making soft pleasurable little noises when Erwin finds an especially sensitive spot.

Erwin continues his exploration of heated skin, kissing his way down Armin’s chest, stopping to tease his pretty pink nipples with lips, tongue and teeth. He enjoys the way Armin wiggles and the hitches of breath when he sucks hard at the tender little nubs.

Armin tugs lightly at Erwin’s hair when the stimulation gets to be a little too much, and Erwin leaves off to nip soft bites down the skin of his abdomen on his way down to Armin’s hip.

Erwin lowers himself back down into his chair and licks at the crease of Armin’s thigh and Armin leans back on his elbows to watch Erwin’s head moving between his legs. Erwin grips the inside of Armin’s thighs and pushes them wider as he noses over to run his tongue over Armin’s balls and gently suck them into his mouth. He rolls them on his tongue as Armin keens and his cock gives a violent twitch. He releases them to take Armin’s cock into his mouth and only manages to bob his head a few times before Armin cries out and cums hot against his tongue.

Erwin swallows around him and runs his tongue along the length of him to clean up a bit before he lets Armin slip from his mouth. He runs his hands up and down Armin’s legs while he recovers, pressing light kisses to his thighs and wherever else he can reach.

As Armin recovers, his muscles tense and he pulls his had up to his mouth. “I’m…”

Erwin turns his attention to Armin’s face and rubs his lightly stubbled cheek against the inside of his thigh. “What is it?”

Armin shivers a bit at the sensation and tries to elaborate. “I’m sor… I,” he waves his hand in Erwin’s direction, “in your mouth.”

Erwin smiles and nuzzles a bit harder. “That’s nothing to apologize for. I expected that.” He moves to suck a mark near the crease of his thigh. “I _wanted_ that,” he growls. “You were so good, Armin. So good for me.”

Armin shivers and reaches out for Erwin, not quite able to make himself sit up yet. Erwin stands and leans forward to embrace him, planting soft kisses along his jaw. When he reaches Armin’s mouth, Armin doesn’t hesitate to kiss him deeply, tasting himself on Erwin’s tongue. 

Armin lets out a breathy moan when he feels Erwin’s hips press against him, his cock hard and straining against the pants he’s still wearing. He wraps his legs around Erwin and thrusts against him, his own flesh beginning to harden again.

Erwin pulls his mouth away with a curse and presses his temple to the side of Armin’s head. “May I take you to bed?” he breathes into his ear, licking the shell of it and sucking lightly at his lobe.

“Yes,” he moans, “yes, please…” His legs unhook from Erwin’s hips as the man stands and Armin is scooped up into Erwin’s arms and carried toward his bedroom.


	2. Chapter 2

Erwin kicks the door closed behind him before depositing Armin on the bed. When he has him situated to his liking, Erwin crawls over him, knees planted on either side of Armin’s legs, and resumes kissing his puffy lips. He plants one arm on the bed to support himself while his free hand tangles in Armin’s hair.

Armin’s hands grip Erwin’s jaw as he opens his mouth wide to lick and suck at his tongue. Deciding he hasn’t felt nearly enough of Erwin’s bare skin, he trails his hands down Erwin’s chest and abs, making a sound of displeasure when his fingers meet the waistband of the pants Erwin still wears.

He fumbles blindly at the front closure until he gets it unfastened and slips his hand through the opening. He grips Erwin lightly through his underwear and Erwin groans and bucks his hips forward. Armin gasps in response and strokes over the hard length of him, only faintly registering his own hips straining up off the bed.

Frustrated by the limited space he has to work with, Armin withdraws his hand and starts pushing at the waist of Erwin’s pants. “Off,” he huffs, “take them off.”

Erwin hums his assent and reluctantly stands to shuck the rest of his clothes, smirking a bit when he sees Armin’s cheeks redden again as he gets his first look at Erwin’s cock. Climbing back onto the mattress, he takes Armin’s ankles in his hands and pulls his legs open far enough to kneel between them, running his big hands up the length of Armin’s legs. Erwin leans forward to mouth at his pretty pink nipples and suck a trail of kisses up Armin’s neck to his ear. “So pretty,” he rasps, biting the sensitive skin behind Armin’s ear. “I want to touch every inch of you.”

Armin moans as heat pools in his gut and he turns his head to catch Erwin’s lips again. He pulls at Erwin’s shoulders, wanting to feel the weight of his body pressing Armin into the bed.

Erwin complies, pinning him down and ravaging his mouth until Armin is breathless and panting for air. “Will you roll over for me, sweet boy?”

Armin’s cheeks color, but he nods in response and Erwin helps him maneuver onto his stomach while Erwin keeps his place on the bed. Once he’s settled again, he feels the steady pressure of Erwin’s hands smoothing up his back, spanning almost the entire width of it.

Erwin sucks and bites at the back of his neck, trailing wet open-mouthed kisses down his spine as he shuffles further down the bed. His large hands grab and squeeze at Armin’s ass cheeks, planting kisses there too.

Armin’s hands clench in the sheets as Erwin spreads his cheeks and presses his tongue flat against his puckered opening. He twitches and mewls as Erwin lavishes attention there, licking and sucking at the crinkled skin. 

Erwin works the ring of muscle, slow and insistent until it opens on the tip of his tongue. He works his tongue inside slowly, pushing straight in and curling on the way out, sucking lightly before pushing in again, deeper. Armin keens above him, his hands scrabbling at the pillows, mouth open and panting between moans.

By the time Erwin manages to work his entire tongue into his ass, Armin is rutting his hips jerkily down into the mattress and gasping Erwin’s name almost continuously. Not wanting this to end prematurely, Erwin pulls back and grasps Armin’s hips to tug them up off the bed. Armin whines in protest, mostly lost in his pleasure with his face pressed to the pillow.

“Shh…” Erwin whispers to him as he bends forward, pressing against Armin’s back to kiss his shoulders. “Let me take care of you, hmm?” He wraps his body around Armin’s, his thick cock pressing into the cleft of Armin’s ass. He grinds against the spit slicked heat of him and licks into Armin’s ear. “I want to make you feel good.”

Armin moans and nods his head as best he can against the pillow. “Erwin,” he rasps, “Please, please, please…”

Erwin’s hand snakes down to Armin’s ass again, his thumb pulling him open gently. “May I kiss you some more, sweet boy?”

“ _Yes_ ,” he breathes, “Erwin, _please_.” He presses his hips back against Erwin, trying to urge him on.

“Good boy,” Erwin practically growls, making him shiver. “Such a good boy for me,” he speaks against his back, kissing his way back down Armin’s spine. He takes a moment to admire his work so far, pulling at the pink rim to see how far he can comfortably open it. Deciding he’s happy with his progress, Erwin gathers spit in his mouth before bending to thrust his tongue inside once again.

He wants this to last forever, but his own cock throbs, hanging heavy and neglected between his legs. Erwin wraps a hand around himself, meaning only to give himself a few slow strokes to tide him over, but with Armin moaning and clenching around his tongue, he finds himself dangerously close to orgasm. He gives a firm squeeze to the base of his cock and holds it, buying himself a little more time.

Armin loses all sense of time, the slick, velvety heat of Erwin’s tongue fucking into him for what seems like hours. Days. Literal fucking _years_ of bliss. His throat feels dry and raspy from his near constant moans and whimpers. His neck is starting to cramp from the way he’s been pressed into the pillow, but when he shifts his head to relieve the pressure, he looks down between his legs and catches sight of Erwin fisting his own cock.

The reaction is almost immediate. His balls tighten and he cries out, “ _Erwin! Erwin I’m…_ ” His voice cuts off as he’s flipped onto his back, Erwin diving in to swallow his cock as he yells, pulsing his release once again into the heat of Erwin’s mouth. His fingers dig into Erwin’s scalp, tugging his hair as he thrusts weakly through the end of his orgasm, eyes clenched shut and mouth open, his breath caught in his lungs as the pleasure overwhelms him.

Erwin swallows everything he’s given and then kneels between Armin’s legs, stroking himself while admiring the state the boy is in. His flushed sweaty skin, his blown pupils, his harsh breathing, his cock slowly softening against his belly. He’s watching Erwin’s fist as he works it swiftly over his shaft, squeezing at the head of his cock every few strokes. Armin stares and licks his lips and the thought of his mouth on Erwin’s cock is what ultimately does him in. He thrusts hard into his hand and comes over Armin’s torso, cock and balls, muscles clenched and breathing hard. After one last pull, Erwin leans forward with his clean hand planted on the bed to pepper Armin’s face with kisses while lightly rubbing his cum into Armin’s belly with his free hand. “You look so good like this, Sweetheart. Flushed and sated and mine,” he purrs.

Armin kisses him then, wet and lazy and content. He blinks slowly at Erwin when he pulls away to wet a rag in the washbasin and nearly starts to drift off while Erwin cleans them both. He nestles into Erwin’s chest afterward, Erwin’s hands rubbing a soothing pattern into his back and whispering sweet words to him as he falls asleep.

**Notes for the Chapter:**

> Does anybody want specific tags on this? It would probably only wind up being a 2 page list of sex acts.


	3. Chapter 3

“Commander,” Armin calls as he steps into the stables, “you wanted to see me?”

Erwin has his back to him, strapping a bedroll behind the saddle of Armin’s horse. “Perfect timing, cadet.”

Armin’s brows dip as he watches Erwin finish checking over his work. “Am I going somewhere, Sir?”

Erwin motions Armin to walk ahead of him as he leads the horse outside to where is own is already waiting. He turns the reins over to Armin with a smile. “Special assignment. We’ll have to ride out now in order to arrive before nightfall.”

Armin nods once as Erwin’s hand falls away. “Understood, Sir.” 

-

It really was a beautiful day for a ride. With a clear sky and a steady breeze, it seemed like no time at all before Erwin slowed to a stop at the top of a small hill. Armin’s eyes grew large as he surveyed the land below. There, surrounded by gently rolling hills, was a field of wildflowers with stunning shades of blue, pink, purple and red swaying lightly above soft grass. 

He makes a mental note to ask Erwin if they can find this place again tomorrow on their way back to base, but the sun is low in the sky and they should be on their way again. He looks to Erwin to see if he’s ready to move on, only to find his gaze already on Armin.

“Do you like it?” he asks, tipping his head in the direction of the meadow below.

Armin nods, taking another look. “It’s beautiful.”

Erwin gives his horse a light kick and starts making his way down the hill. “Good,” he calls behind him, “let’s get a closer look.”

It’s just as beautiful up close, but Armin is starting to get a little antsy about holding them up any longer. Erwin doesn’t seem to be in hurry, but… “How much farther are we travelling tonight?”

Erwin smiles and looks somewhere over Armin’s shoulder. “About that far.”

Oh. He hadn’t seen that before. Hidden next to a short row of trees and snuggled up against the base of one hill is a small cabin. It might be the most perfectly situated home he’s ever seen. “Are we meeting someone here?”

Erwin shakes his head and rides toward the cabin, dismounting and waiting for Armin to do the same before pulling him into an embrace. “I have a confession to make,” he mumbles into Armin’s hair.

Armin wraps his arms around Erwin’s waist and scratches his nails lightly against his shirt. “Oh? What’s that?”

“There is no special assignment. It was just an excuse to bring you here.”

‘Here’ turns out to be Erwin’s secret hideout. He’d purchased it a few years ago with a bit of the money he’d saved over the years, but only visits sporadically. Aside from Armin, the only other person who knows about it is Levi, who needs to be able to find Erwin in case of emergency.

Armin is asked to take care of the horses after Erwin grabs their supplies and heads inside to air out the house and get dinner around. He finds a pump beside the house for fresh water and a smallish coral where the horses can be kept tonight, but after they’re tended, he lets them loose to roam through the flowers and nibble at tall grasses.

He finds Erwin lounging on a blanket laid out in the shorter grass near the cabin. Their supper has been unpacked as well. He spies bread, cheese and freshly sliced apples lying atop a wooden block and a small thermos sitting next to it.

Erwin beckons Armin closer, pulling him down to nestle into the space between Erwin’s bent legs when he’s within reach. Once he’s settled, Erwin rubs his cheek against Armin’s temple and speaks softly into his ear. “Do you approve?”

Armin smiles and turns his face up to kiss Erwin sweetly. “It’s lovely. Thank you.” After one more kiss, Armin reaches for a hunk of cheese and feeds a bit to Erwin before trying it himself. Erwin seems surprised and very pleased to be fed this way, so Armin repeats the action with a slice of apple. He finds that he gets a certain sort of satisfaction from spoiling Erwin this way. 

It’s especially satisfying when Erwin uses his tongue to chase the juice running down his fingers. A light flush stains Armin’s cheeks and he unconsciously licks at his bottom lip as he watches Erwin’s mouth licking and sucking at his fingers. Feeling a bit parched after that, he reaches for the thermos. He’s expecting water, but when he tips the bottle, he finds a deep crimson liquid filling the cap.

He presses the cup to Erwin’s lips and tilts it forward, watching Erwin’s throat bob as he swallows. A bit of the liquid escapes the corner of his mouth, but Armin catches it with a swipe of his thumb and brings it to his own mouth to taste. He finds it pleasantly sweet and takes a couple sips for himself before tending Erwin again.

Armin quite enjoys this hedonistic style of dining and easily loses track of everything else as they continue their meal. At some point their bellies have been filled and the remaining food is forgotten in favor of trading slow kisses and soft caresses. Armin currently has his eyes closed and his head tipped to the side while Erwin licks and nibbles at his neck. A loud snort directly in front of his face has them jerking apart and when Armin opens his eyes, he’s nose to whiskery nose with Erwin’s horse. The moment he meets Erwin’s wide eyes, Armin breaks down in a fit of giggles.

With the mood effectively disrupted, Erwin huffs a laugh and gives his horse a firm pat. “Alright, we’re going.” He lifts a still giggling Armin from his lap and presses a kiss to his head before heading out to corral the horses for the night.

Armin picks up the rest of their food along with the thermos and blanket and heads inside. It’s getting a little chilly with the sun setting, so after he covers the food he moves to get a fire started in the hearth. He’s almost finished when Erwin comes in, immediately heading towards a small door at the back of the cabin, telling Armin he’s going to wash up. 

As the fire grows, Armin discards his jacket and boots and sits on the edge of the bed. Erwin has spread one of their bedrolls out over the mattress and placed the other at the top of the bed to be used as a pillow. The fire probably won’t be enough to keep them warm all night, so Armin retrieves their picnic blanket and lays it out at the foot of the bed. He’s just finished smoothing it out as Erwin exits the washroom.

Armin can’t help but stare as Erwin walks out in nothing but his underwear and places his discarded clothing on a small wooden chair in the corner of the room. His eyes roam over Erwin’s body, feasting on a wealth of bare skin and thick muscle. 

Erwin’s mouth twitches into a sly smile as he watches Armin watching him. He strides over to sweep Armin into a heated kiss, pulling back from Armin’s lips just enough to growl out “Go wash up and come back to me,” before licking forcefully back into Armin’s mouth.

Armin moans into the kiss, a little light headed from the intensity of it. He’s breathing heavily by the time Erwin lets him go and he stumbles a bit toward the washroom. Once inside, he leans against the sink basin and takes a deep breath as he catches sight of his reflection in the small mirror mounted there. He has to laugh at himself a bit for looking just as flustered as he feels.

Eager to rejoin Erwin, he undresses and uses the toilet quickly before washing up as thoroughly as he can without a shower. He lifts his underwear from the pile of discarded clothing and freezes just before stepping into them. His cheeks heat as he considers not putting them back on. He pictures the satisfied, knowing look on Erwin’s face earlier when he saw how Armin looked at him and he wants to turn the tables a little. Maybe it’s the wine, but he’s feeling a little bit braver than usual. 

He drops them back in the pile and opens the door. 

Erwin is lying back in bed waiting for him. He turns his head to the side when he hears the door opening and pauses at the sight of Armin there. His eyes go dark as he pushes up onto one elbow to watch Armin saunter towards him. Erwin had been semi-erect just waiting for him, but watching Armin now, eyes hooded, pink cock firm and bobbing slightly as he moves toward the bed has Erwin achingly hard. 

Armin doesn’t stop when he gets to the bed. There’s no hesitation whatsoever as he puts one knee on the mattress and proceeds to crawl over to Erwin. He throws one leg over and straddles Erwin, wiggling a bit to get comfortable, and leans forward to take Erwin’s mouth. 

Erwin wastes no time getting his hands on Armin's bare skin, thumbing at his nipples before sliding down to grip at his hips. He guides Armin's movements until he’s rocking slowly against him, his cock rubbing against Erwin’s abs.

Armin loves those abs. He loves feeling them, but he wants to see them too. He pulls out of the kiss to nibble at Erwin's bottom lip before sitting back on Erwin’s lap and taking a long look. He rotates his hips a bit, grinding down against Erwin just to see his reaction. He’s not disappointed as Erwin’s muscles tense and his eyes flutter closed. Armin slides his fingers under the waistband of Erwin’s underwear and tugs. “Can I take these off?”

With permission given, Armin climbs off of Erwin to carefully remove them and toss them over with the rest of his clothes. He takes a long look at Erwin, eyes roving every part of his exposed body. Kneeling next to Erwin on the bed now, he runs one hand up Erwin’s thigh, curling his fingers to scratch lightly through the soft hair there. He reaches farther to squeeze at the inside of his thigh, tugging a little to encourage Erwin to spread his legs so his fingers can continue their journey north. When he reaches the top, he stretches his fingers out to skim over Erwin’s balls and run his fingertips lightly up the underside of his cock. He hears a soft exhale and looks up to see Erwin’s eyes on him.

“Erwin,” his eyes flick back to his hand on Erwin’s cock, “… can I kiss it?”

Erwin's cock twitches hard against his fingers as he sucks in air. “Yes. Fuck, Armin,” he rasps, “we can do anything you want.”

Armin bends forward, spreading his knees for better balance, one pressing against the side of Erwin's waist and the other against the outside of his thigh. He wraps both hands around the base of Erwin's cock. It’s intimidating this close up. He’s so much bigger than Armin, but that was pretty much a given. Taking a steadying breath, he lowers his head and places a soft kiss directly to the tip. The skin there is warm and smooth and he quite likes the feeling of it against his lips. Curious, he opens his mouth to lick over the head. Even better.

He tries to fit the tip into his mouth next, but it’s too dry and his lips don’t slide down very far. He pulls off to lick at his lips and gather some saliva in his mouth before licking over the head again, getting it as wet as possible. He’s able to fit the entire head in his mouth this time and sucks at it lightly, his tongue pressing against hot skin.

He can see Erwin's hand gripping at the bedroll and hopes that’s a good sign. He looks over and sees Erwin's head tipped back and eyes squeezed shut. “Erwin,” he calls softly, getting Erwin's attention “am I doing it right?”

Erwin lifts his head and reaches down to squeeze and rub at Armin's leg, since it’s the closest thing within reach. He’s breathing though his mouth and pauses to swallow before speaking. “You’re doing so well, Armin,” he answers, voice low, “feels amazing.”

Encouraged by Erwin's praise, he returns to his exploration, opening his mouth to cover Erwin's cock in wet sucking kisses. He licks down to the base of his shaft and back up again, getting it wet so he can try to take more into his mouth. He keeps getting his hair in his mouth when it sticks to the wet skin. Erwin must notice him struggling with it, because he reaches out to gather Armin's hair in his hand and hold it back at the crown of his head.

Free from this distraction, Armin pops the head of Erwin's dick in his mouth again and moves further down his shaft. It’s much easier this time and he moves his head up and down, taking in more with every downward motion. He flicks his eyes over to check Erwin's expression again and the ravenous look on his face makes Armin moan.

Erwin's hand tightens in his hair. “Ngh, Armin, fuck…” He catches Armin watching him, his pupils blown and mouth stretched wide. “You look so pretty like that.”

Armin's eyes flutter closed and his hips give an involuntary thrust when Erwin praises him.

Erwin runs his free hand up to squeeze at Armin’s ass cheek while he watches him take more and more into his mouth. “Do you like it, Baby?” he croons, “Do you like sucking my cock?” 

Armin flushes and makes a keening noise in the back of his throat. He’s moving his hips again, pushing back against Erwin's hand.

“Armin,” Erwin runs his hand up Armin's back and lightly massages the back of his neck to get his attention, “I want to make you feel good too. Will you let me?”

Armin hums around him and pulls off with a pop, sitting up and letting Erwin manhandle him. He’s spun around so that he’s straddling Erwin's chest, his ass on full display while he renews his efforts to swallow Erwin's cock. He tucks his hair behind his ears as best he can and takes Erwin in hand again.

Erwin runs his hands up the back of Armin's thighs and grasps his cheeks. His hands really do look large against Armin's smaller figure, each ass cheek fitting perfectly into his cupped palms. His hands flex and he barely manages to stop his hips from bucking when Armin wiggles his tongue into the slit of his cock. He feels a deep rumble in his chest when Armin adds suction to his probing exploration, moaning as Armin slides his mouth lower. He can’t take it all yet, but he’ll get there.

Erwin's hands roam over Armin's pale skin, everywhere he can reach. Armin's mouth on him feels incredible. So much better than he would have ever expected for his first time out. Erwin is trembling a bit, trying to keep his hips still. “Feels good, Sweetheart,” he breathes, “So good for me.” 

Armin moans again and Erwin sees the way his pretty cock jumps as he pushes Erwin to the back of his mouth. “So good, Baby, just like that.”

Armin can’t help but be a little embarrassed in this situation. Not because he feels salacious or wanton, but because he _likes_ it. He likes the way those filthy things slip from Erwin’s lips, likes the way his voice gets deep and rumbly, the breathlessness, the _awe_ , like he can’t quite believe it’s happening either. He likes knowing that Erwin feels good, that he wants Armin to feel good. He likes the way his heart flutters when Erwin calls him Sweetheart, likes the way his cock twitches when he calls him a good boy.

He’s embarrassed because he’s never suspected this of himself, never considered the possibility he could be so turned on by a little dirty talk. It’s not as if he’s never heard it before. He’s constantly surrounded by horny teenage boys, after all, but it’s never been directed at _him_. He never paid much attention to their fantasy and bravado because he honestly never pictured himself in this situation. It seemed like a waste of time when they all had much more important things to worry about.

The things coming out of the Commander’s mouth now are _filthy_. Armin never would have imagined those things ever being spoken, even thought of, by Erwin. It’s such a contrast to his general demeanor that it’s almost as if this Erwin, _his Erwin_ is an altogether different person than the one everyone else knows.

Erwin scratches his short nails lightly down Armin's ass and thighs, the trails turning white and then pink. “So pretty here too, Armin, with your pale skin.” Erwin runs his thumbs up between Armin’s ass cheeks, pulling them apart. “But you’re pretty pink right here,” he growls, rubbing his thumb over the crinkled skin of Armin's hole.

Armin moans and pushes back into Erwin's hands, beginning to feel a bit desperate for more direct stimulation. “Erwin,” he whines, rocking his hips, “more...”

Erwin reaches for the handkerchief he stashed under their makeshift pillow and unravels it to reveal small bottle of scented oil. After coating his fingers, he rubs against Armin's hole again, putting more pressure on it this time. He bites his lip as he watches the tip of his finger disappear into the tight opening, feeling Armin tense for a moment before relaxing again. He rotates his fingertip in tiny circles, rubbing deeper and deeper until it loosens enough to slip his entire finger inside. Erwin thrusts it slowly in and out, curling his finger on every other withdrawal. Once Armin has completely relaxed around him, he pushes in all the way and starts rotating his finger again, the thickest part spiraling out against the ring of muscle. 

When he pulls out for more oil and pushes back inside with two fingers, Armin makes a whining sound and withdraws from Erwin's dick. Erwin tries to sooth him with whispered encouragements as he reaches down to caress Armin's cock with slow, firm strokes. “Is this alright, Armin? Is it too much?”

Armin shudders and shakes his head where it rests against Erwin's thigh. “Just keep, ohh… keep touching me?”

“Of course, Sweetheart,” he murmurs, voice soft. “Tell me if it’s too much.” He twists his hand against the head of Armin's cock, and when Armin bucks and moans, he starts shallowly thrusting his fingers into that tight heat again.

Armin rubs his cheek against Erwin's cock while he’s getting used to the stretch in his backside, the stinging sensation he felt overpowered by the feeling of Erwin's hand rough on his dick. 

Erwin can feel Armin’s panting breaths against the still damp skin of his cock as Armin rubs his open lips up and down the shaft. “Look at you,” he growls. “So sexy, Armin.” He twists his fingers, rubbing against his inner walls. “You feel so hot inside, so soft.”

Armin shivers at the gravelly sound of his voice and laps at Erwin's cock. He covers it in broad, wet licks before taking him in, pushing all the way down until it bumps the back of his throat and then sucking on his way back up. Erwin's hip twitch up, following the heat of his mouth, and Armin does it again.

Erwin fucks his fingers deeper into Armin's ass, matching the steady rhythm of Armin's mouth on him. When he’s far enough in, he curls his fingers toward Armin's belly, searching until Armin jolts and clenches hard around the digits.

He shakes and whimpers when Erwin rubs over that spot again with purpose. His blowjob is getting sloppy, drool running down Erwin’s length as he concentrates more on the feeling of Erwin's fingers inside him. It feels incredible, but not enough somehow. He rocks his hips back, grinding down on Erwin's fingers, a fervent desire to be filled.

Erwin is very much on edge due to the almost constant vibration of Armin's moans on his cock. The sight of Armin practically riding his fingers isn’t helping either. He crosses his fingers inside of Armin, stretching him a bit more. When Armin practically sobs and thrusts back even harder, Erwin reaches for the oil again. “You want another finger, Baby?” Not daring to remove the fingers already inside, he pours a generous amount of oil down the crack of Armin's ass and gives him a third finger.

Armin keens at the easy glide of Erwin's fingers inside him. He feels so full, the stretch wonderfully intense. He takes the third one much quicker than the first two, hardly slowing his hips as he shoves back against Erwin's hand.

Erwin is rock hard in his mouth and Armin wraps his hand around the base of his cock, pumping his fist in time with the bobbing of his head. He hears Erwin grunt and his fingers plunge into him a bit harder. Armin uses his other hand to reach down and fondle Erwin's balls, rolling them in his palm and squeezing gently.

Erwin throws his head back and cries out, “Ngh, Armin… Armin, I’m going to cum.” His breathing is ragged and interspersed with choked off moans. “If you don’t want it in your mouth, you have to pull off now.”

Armin keeps going, sucking harder, moaning louder, and Erwin is lost. “Here it comes, Baby,” he warns. “Mmm, here it comes, are you gonna swallow it down for me?” On the verge of release, he lets go of Armin's dick to dig his fingers into the mattress. “Fuck, _Armin_ , swallow it down like a good boy,” he growls as his orgasm overtakes him, spurting hot and hard into Armin's mouth.

Armin swallows as much as he can when Erwin floods his mouth, but some inevitably dribbles out to pool on Erwin's groin. Erwin carefully extracts his fingers and turns Armin around, repositioning him so that he’s kneeling over Erwin's face.

Erwin grasps his hips and guides him forward, sucking Armin's cock into his mouth and urging Armin's hips into a rocking motion. He reaches behind Armin and sinks his fingers back inside while Armin thrusts helplessly into Erwin's mouth. 

His rhythm is erratic, overwhelmed by the purely carnal pleasure of thrusting back onto Erwin's fingers and forward into his mouth. He’s practically sobbing by the time he curls around Erwin's head, white-hot sensation spreading through his body as he cums down Erwin's throat.

Armin collapses onto his side, body still mostly curved around Erwin at the head of the bed. They’re both breathing heavily as Erwin tugs the handkerchief out from under Armin's leg and uses it to wipe them both down. When he’s finished, he sets it on the small bedside table along with the oil and stretches out on the bed with Armin a warm weight against his side.

“Mmm… ‘s really good,” Armin mumbles against Erwin's chest while Erwin runs his fingers through his hair.

“I hope you still feel that way during the ride back tomorrow,” he smirks. “I was a little rougher than I intended to be.” 

Armin makes a displeased sound and pinches Erwin's side.

Erwin jolts and huffs a laugh before placing a soft kiss on the top of his head. “Sleep well, Sweetheart.”

**Notes for the Chapter:**

> It's late and I'm tired, so feel free to point out any mistakes. I just wanted to make sure I got it up for you guys tonight. ( ͡° ͜ʖ ͡°)


	4. Chapter 4

It feels as if he’s been here for hours, for days, spread out on Erwin's fingers and writhing in the sheets. He’s lost to the feeling of thick fingers stretching him wide and Erwin's stubble scratching at his neck and cheek as he whispers about all of the filthy things he’s imagined doing to him.

Usually they’d be finished by now, tangled up in each other as the sweat cooled on their skin, heartbeats returning to normal. Tonight, though… tonight it’s not enough. Tonight Armin wants, _needs_ more.

*****

When Armin entered the office, Erwin assumed a casual pose, sat half on the desk with one leg on the floor for balance and the other bent at the knee and dangling from the edge. Armin had only intended to hand over a stack of papers from Hange (and maybe snag a quick kiss before bed), but one glance at Erwin made him question those plans. 

Armin knew that look: his head cocked slightly to the side, the slight upturn at the corner of his mouth, eyes gleaming with intent. Armin placed his fingers on the lock and raised an eyebrow at Erwin, questioning. When Erwin’s smirk only grew, he flicked the lock into place and set the documents in their usual spot on Erwin's desk.

Erwin opened his arms, wrapping them around Armin when he stepped close enough. He buried his face in Armin's hair and breathed deep, relaxing against him. Armin melted into him with a hum, enjoying the closeness.

After a moment, Erwin pulled back just enough to guide Armin into soft, sweet kiss. His lips were supple and warm and just… “Perfect.” 

Armin smiled up at him, pleased. “I should let you get back to work,” he sighed, leaning up for one more kiss. He turned to leave, but only made it about one and a half steps before Erwin caught him and pulled him back in, hugging Armin's back to his front. Armin stumbled back with a soft yelp and laughed when Erwin pushed his face into Armin's neck.

“Don’t go,” he grumbled against soft skin. Erwin kissed and nibbled at his neck, his giant hands splayed across Armin's belly and chest. When he didn’t protest, Erwin pulled Armin harder against him, pressing his fingers deeper into Armin's flesh, holding him tight.

Armin moaned quietly and tilted his head to the side, giving himself over to Erwin. He felt cherished and safe and _wanted_. “Mmm… I love the feeling of your hands on me.” He guided one of Erwin's hands down to his groin and pressed his hardening cock against Erwin's palm. “Take me to bed?”

*****

“Erwin,” he whines, panting for breath. “Erwin, in me. Please.”

They haven’t gone that far yet. Armin has asked for it a few times, usually during those occasions when he was worked up and Erwin was growling detailed fantasies into his ear. They both want to take this next step, but Erwin is being cautious. Overly cautious in Armin's inexpert opinion, but he wants to make sure Armin enjoys the experience to the fullest. He insists on spending their stolen moments slowly working Armin open, giving him a little more each time, stretching him wider and wider on his tongue and fingers. It’s a practice Armin has silently dubbed his ‘special training’.

Currently, Erwin has four fingers plunging into him. The easy glide has Armin driving his hips down, meeting each thrust and wanting more. He pulls Erwin's face up to look into his lust filled eyes. “I’m ready, Erwin, please. I want you.”

Erwin licks his lips as he studies Armin’s face, looking for any signs of discomfort. He spreads his fingers wide, watching Armin's eyes flutter as he moans.

“Okay,” he assents, slowly withdrawing his fingers. He sweeps down to kiss Armin deeply while he reaches for the oil. “Tell me if you want me to stop.”

“I will,” Armin assures him, pulling him into another kiss. He can feel Erwin's arm moving as he coats himself with oil. The realization of what’s about to happen draws a moan from deep in his chest as he sucks happily at Erwin's tongue.

Erwin kneels back between Armin's legs and urges his hips up long enough to tuck a pillow under him. He presses the head of his cock against Armin's lax opening and looks up to catch Armin watching intently, pink cheeked and breathing heavily through his mouth. “Ready?”

Armin can’t look away. He’s never seen anything so lewd, could never have even imagined the sight before him. Commander Erwin Smith is kneeling between his splayed thighs, his perfect hair mussed from Armin's fingers, pupils blown wide, sweat glistening on his corded muscles, holding his hard prick in his fist. Armin nearly loses it then and there. “Fuck, Erwin, do it,” he rasps.

Erwin pushes forward with a grunt and slips inside. His eyes fall closed as he presses deeper, the hot, slick grip on his cock making him impossibly harder.

Armin gasps, his back arching, gripping tightly at the pillow under his head. It’s intense. He doesn’t know how else to describe it, can’t pick apart the jumble of sensations he’s feeling, but he wants more. He whines high in his throat, squirming at the overload of his senses as Erwin's cock pushes deeper into him. He’s so full. So full and hot and it seems like it’s never going to end. “It’s so big,” he whines.

Erwin mentally chastises himself for being so turned on by that. He forces himself to go slow when everything in him screams take, own, more, now. “Is it too much?” he pants. “Do you want me to stop?”

“No,” he whimpers, “I want it.” His hand shoots out, reaching for Erwin. “I want it.”

Erwin drops down onto his forearm, pushing his tongue into Armin's open mouth and using his free hand to rub and pull on Armin's nipples. When Armin starts letting out soft, breathy little moans around Erwin's tongue, he pushes the rest of the way inside.

Erwin moves his hand down to rub lightly against Armin's belly. “I’m inside you Armin,” he rasps. “All of me.”

Armin whines, squeezing hard around Erwin's cock. Erwin moans and barely stops himself from jerking forward. He cups Armin's cheek and kisses his plump lips. “Feels so good, Baby,” he whispers. When he feels Armin relax again, he gives an experimental thrust. The delicious little sounds he gets in response spur him on until he settles into a decent rhythm.

His free hand continues to roam Armin's body, delivering every bit of extra pleasure Erwin can give him while he fucks steadily into him. Armin is rocking up to meet his thrusts now and making the sweetest sounds Erwin has ever heard.

“Fuck, Baby, you’re taking it so well,” he praises. “So good for me.” He watches Armin's eyes go dark, pupils expanding until there’s only a thin ring of blue. “Do you like it, Armin? Like being filled up?” he huffs as his hips snap faster.

It takes Armin a minute to adjust to the new rhythm, but he gets it soon enough, bucking up to meet Erwin's thrusts with enthusiasm. 

The force of it makes Erwin groan. “That’s it, Sweetheart,” he pants, “fuck me with that tight, sweet little hole.” 

Armin's gut tightens in response and he moans Erwin's name. Erwin shifts to get better purchase on the bed and the resulting angle of penetration makes Armin wail, nails digging into Erwin's shoulders as his cock jerks hard. 

Erwin continues his assault on Armin's prostate as Armin writhes and moans Erwin's name continuously. Erwin reaches down to wrap his hand loosely around Armin's cock. “That’s it,” he croons, “that’s my good boy. Are you ready to come, Baby?” He licks into Armin's open, panting mouth and bites at his lower lip. “Will you come for me, sweet boy? Mmm, want to feel you come on my cock.”

Armin feels like a whimpering mess. The obscene things coming out of Erwin's mouth and the thick cock pounding into his sweet spot have made him mindless with pleasure. Nothing else exists in this moment. He’s so close. So close. He struggles to voice his need. ”Y- yes, yes,” he cries. “Erwin! Make me c… make…” he whimpers in frustration, “more…”

Erwin adjusts his grip on Armin's cock, gazing down at him. “Beautiful,” he breathes. “You’re beautiful, Armin.” His rhythm falters as he snaps his hips faster. “Fuck,” he groans, “my beautiful boy. Mine.” 

Erwin twists his hand around the head of Armin's cock as he slams hard into his prostate and Armin shatters. He comes hard, his eyes rolling back as his whole body trembles, pulse after pulse of come shooting between them.

Erwin fucks him through it, groaning as Armin pulsates around him. He holds on just long enough for Armin to finish before he grinds into him as deeply as possible and comes. His head drops to Armin's shoulder as he convulses and pants for breath. 

Armin has nearly been lulled to sleep by Erwin's sweet, whispered praises when Erwin slips out of bed to get a wet cloth. Armin doesn’t complain too loudly because he feels vaguely gross and thoroughly worn out. He’s rewarded with sweet kisses and soft words as he falls asleep cradled in Erwin's strong arms.


	5. Chapter 5

**Summary for the Chapter:**

> There’s a joke to be made about a survey mission inside these walls, but he doesn’t want to ruin the mood. Maybe he’ll save it in case he’s ever pressed into sharing his experiences by his fellow recruits.

Armin is laying belly down on Erwin's bed, lazily flipping through a book when Erwin finally makes his way into the room. Armin hears him sigh and looks up to see him running a hand through his hair. Probably not for the first time today, from the looks of it. His gear is already off and his boots dangle from one hand. 

He aims a soft, tired smile at Armin before he deposits his boots by the dresser and sits on the edge of the bed, unbuttoning his shirt as he goes.

Armin reaches over to put the book away and then curls himself around Erwin to lay his head in his lap. He hums contentedly when Erwin's fingers start running through his hair. “Mmm, everything done?”

“As much as it ever is,” he replies, tugging lightly at Armin's hair.

Pushing himself up on his hands, Armin tilts his head up for a kiss. Erwin bends forward to meet him, but stops before he can reach, flinching and pulling back. “Sorry,” he responds to Armin's look of concern, “it’s my back.”

Armin stands up on his knees and sweeps stray hair out of Erwin’s face to press a kiss to his forehead. “You work so hard,” he whispers against his skin. He pulls back to study his handsome face, now held in his hands. He rubs his thumbs lightly over Erwin's cheek bones and down his jawline before kissing his mouth with a slow, firm push of lips. He kisses him several more times, soft and lingering before sitting back and pushing Erwin's shirt down off his shoulders. “Let’s see if I can make you feel better.”

Once Armin coaxes his shirt completely off, he instructs Erwin to lay face down on the bed and takes the new bottle of oil from the nightstand. He settles himself gently atop Erwin's butt and pours some into his cupped hand. It’s scented this time, he notices. He passes it under his nose a few times, inhaling. Chamomile, he thinks. 

After warming the oil in his hands, he gets to work spreading it over the broad expanse of Erwin's back. It glistens in the low light of the room, creating glowing highlights and soft shadows that play about the contours of well-defined muscle. 

He’s so focused on the visual that he fails to realize his shirt has been dragging across Erwin's lower back until it’s too late. He sees the stain spreading from the hem of his shirt to the waistband of Erwin's pants. “Damn it,” he mutters under his breath. He bites his lip and flips through a mental catalogue of possible solutions. The most obvious one is also the most appealing, so Armin goes with it. He wipes his hands on the conveniently placed towel they use for their, ahem, _intimate moments_ and shrugs out of his soiled shirt.

He pats Erwin's hips, tells him to lift so he can reach around to unfasten them, and begins to work them slowly down and off. He does the same with his underwear and hops down to shed the rest of his own clothes before climbing back up to his original position.

He goes to work on Erwin's neck first, fingers sliding down the sides while his thumbs push up the middle into his hairline. When the muscles there start to feel a little softer, he works his way over Erwin's shoulders and down his arms. Reaching that far without putting any weight on Erwin's back takes a little more balance than he anticipates, but he’s got the core strength for it thanks to his 3DM training. It also has the unexpected side effect of his nipples rubbing against Erwin's oil slicked skin. He wonders if Erwin can feel how hard they are from the near constant stimulation.

When he’s finished there, he digs his fingertips into Erwin's back and drags them all the way down to his waist where he flattens his hands and pushes his thumbs down on either side of Erwin's spine, sliding all the way back up again. Erwin lets out a satisfied hum, nuzzling into his pillow. 

He does this a few more times until he starts to feel where the knots are. One by one, he works out those spots, kneading into the muscle and smoothing his palms over heated skin when they’ve gone soft again. He whispers apologies when Erwin hisses or tenses up, but keeps working until he’s dealt with them all.

“There,” he soothes, “we’re okay now.” He runs his hands down Erwin's back and turns his fingers out, gripping and squeezing low on Erwin's waist as his thumbs rub circles on his lower back. Erwin moans at that and Armin does it again harder, causing Erwin to let out another pleasured moan and shift his hips. Armin bites his lip as that sound and the feeling of Erwin's glutes flexing under him cause his half-hard cock to fill.

He lifts up and crawls back a bit to straddle Erwin's thighs before reaching for the oil again. He starts to pour some into his palm, but the bottles slips in his slick hand and spills out onto Erwin's ass before Armin can catch it. 

Erwin jolts at the feeling of cool oil hitting his skin. He hears Armin's breathy “Whoops, sorry,” from behind him and huffs a laugh before relaxing back into the bedding.

Armin stoppers the bottle and licks his lip as he watches the oil slide down between Erwin's cheeks. He reaches out to cup Erwin's ass in both hands, giving it a squeeze before running them up to gather some of the spilled oil. He digs his fingers into Erwin's glutes, rubs and squeezes up to his waist and down his hips. He cups the backs of Erwin's thighs and splays his fingers wide as he pushes up with his outstretched thumbs, applying more pressure, pushing up and up until his thumbs are pulling Erwin's cheeks apart. 

Erwin has been making lazy sounds of pleasure throughout, but gets louder when he feels himself spread open. He’s almost disappointed when Armin moves on to massage his legs, but he’s feeling too complacent to hold onto the thought. He can’t remember ever being taken care of this way.

Armin works his way down each leg in turn and settles at the end of the bed to work on his feet, his thumbs rubbing half circles into the soles. He takes each toe between his thumb and forefinger and pulls gently, smiling to himself when Erwin twitches at the ticklish spots. He takes his time there, rubbing extra oil into the rough patches of skin and massaging along the tendons of his ankles. 

Aside from a few soft sighs, Erwin has been quiet for a while. His body is so lax now that Armin suspects he may have fallen asleep at some point. Armin makes his way back up his body to check, stroking his hands softly over Erwin's pink skin as he goes. 

Just as he makes it far enough to peek over Erwin's shoulder at his face, the head of his dick glides up between Erwin's slick cheeks. A breathy exclamation escapes him and he freezes, caught off guard. 

Erwin grins lazily and flexes his glutes, squeezing Armin between them. “Erwin!” he gasps, digging his fingers into Erwin's shoulders. There’s a dark chuckle from Erwin as he flexes again and Armin's hips thrust in response. 

He looks down to watch himself gliding easily through the cleft of Erwin's ass thanks to the oil he spilled earlier. Armin thinks it almost looks like he’s fucking him except for the pink head that peeks out at the end of every thrust.

“Erwin,” he whispers, licking his lips. “Erwin, I want to put it in,” he confesses, still watching himself move. “I… can I put it in?”

Erwin hums his assent and pushes his ass up a bit. “Give me two fingers first, sweetheart. Lots of oil.” It’s going to be a little tight with only two, but he wants to really feel it. Like he _knows_ Armin must feel it. 

Armin crawls up and leans over Erwin's shoulder, parting Erwin's lips with his tongue for a wet open mouth kiss. It’s maybe a bit aggressive and the angle awkward, but Erwin seems to like it. He pulls back to study Erwin's face. “Your back’s okay?”

Erwin smiles and tilts his head in search of another kiss. “Best it’s felt in years, baby. Thank you.”

Sensing no hesitation from Erwin, Armin nods and takes his mouth again, closing his eyes and savoring the feeling.

He breaks away when he feels Erwin start rutting against the sheets and shuffles down to grab the oil from the foot of the bed where he left it. He looks at Erwin laid out in front of him, gorgeous and pliable and wonders how he got so lucky. 

Armin runs his hands down the inside of Erwin's thighs and urges him to spread his legs so he can settle between them. He gently pulls Erwin's cheeks apart, breathing heavily, transfixed by the sight of Erwin so exposed to him.

Erwin moans into his pillow as Armin's oil slicked fingers tease over him. Armin rubs circles over the puckered skin, applying more and more pressure until his finger dips inside. Encouraged by Erwin's contented sigh, he pushes deeper, amazed at how hot he is inside. 

He works his finger in and out, attempting to mimic what Erwin usually does to work Armin open. After he works his second finger in, he starts subtly (he hopes) trying to find that spot that makes his brain melt. There’s a joke to be made about a survey mission inside these walls, but he doesn’t want to ruin the mood. Maybe he’ll save it in case he’s ever pressed into sharing his experiences by his fellow recruits.

After several minutes, he still hasn’t been able to find it. Based on Erwin's reactions, he must have been close a few times, but never quite managed to reach it. _If my fingers are too short_ , he thinks, _I’ll just have to try with something longer._

He tugs gently at the rim, testing the stretch. It seems loose enough, but he’s not sure. “Erwin?”

“I’m ready, baby,” he rasps, pushing back onto Armin's fingers. “Fuck me, Armin.”

Armin whimpers as he almost loses it right there. He has to squeeze the base of his cock before he can even slick himself up. He positions himself behind Erwin and takes a deep breath before pushing in and _FUCK_ , he can’t _believe_ it. It’s so hot, so tight, so slick, and soft, and Erwin's insides are squeezing his dick and he doesn’t know how Erwin _lasts_ so long. He feels like he’s going to explode already and he’s barely made it inside.

He plants one hand on Erwin's back to hold his weight and watches as his dick disappears into Erwin. They’re both moaning now, and Armin grinds hard into Erwin as he bottoms out and pants, “Fuck, Erwin, fuck, fuck…”

He slides back out, catching the way the oil glistens on his dick as he pumps in and out of Erwin's ass and it’s just _obscene_. Nothing, _nothing_ has ever looked this compelling before. It feels like his entire body is vibrating as his balls slap against Erwin's oil-soaked skin.

He’s trying to keep a good rhythm, knows it feels good when Erwin does it, tries to think past his own pleasure to remember what else Erwin does to make him feel good. He tries changing the angle of his thrusts until Erwin grunts and squeezes down on him.

“Did I get it?” he asks, pushing in again. Erwin's pleasured shout is answer enough as Armin singles in on that spot with every stroke. He pistons his hips, driving into Erwin again and again, sweat rolling down his body and making the slap of skin on skin even louder.

He tries. He really tries to hold himself back, but soon the stimulation proves to be too much. He sobs out Erwin's name as he cums, the tension in his body suddenly releasing as he pulses inside of Erwin.

He’s breathing heavily and trying to make his brain work again when he feels Erwin moving beneath him. He starts to pull out, but Erwin reaches back and grabs his hip in one hand and pulls him back.

“Shit, Armin stay in,” he pants, “stay inside, baby. Can you do that for me?”

Armin whimpers and presses forward against Erwin's ass as hard as he can, considering his whole body feels like jelly.

Erwin clamps down on Armin’s spent cock as he raises his own hips just enough to take himself in hand and stroke himself off fast and hard. 

Armin keeps his still hard cock buried as Erwin undulates his hips, making the head of Armin’s dick rub at that sweet spot over and over until he cums on the sheets. 

Armin's dick twitches hard as he feels Erwin's ass contracting around him. He could probably cum again if only he had the strength to keep going. As it is, he gives a couple hard thrusts and collapses onto Erwin’s back, no longer able to support himself.

He shifts just enough to slip out and wraps his arms around Erwin, holding him as they both try to catch their breath. He’s almost asleep when Erwin's back vibrates under him with a sleepy chuckle.

“Don’t fall asleep yet, sweetheart. We still need to clean up.”

Armin hums and nuzzles against Erwin's warm skin and murmurs an unconvincing “Okay.”

**Notes for the Chapter:**

> Never in the course of my life did I ever anticipate Googling “is chamomile oil safe to use for anal lubricant”.


End file.
